The effect of 6-day courses of terbutaline and ephedrine on the metablic and hemodynamic responses to a 4-hour epinephrine infusion were compared in the same five individuals. Terbutaline suppressed the subsequent lactate response to epinephrine more than ephedrine did. The suppression of blood glucose response to epinephrine was similar for the two drugs. Ephedrine profoundly altered the hemodynamic responses to epinephrine causing significantly higher systolic and diastolic blood pressures and slower pulse. Terbutaline did not alter the systolic blood pressure during subsequent epinephrine infusion, and had less effect than ephedrine on the diastolic pressure and heart rate during the infusion. The effect of terbutaline on physiologic responses to exercise was studied, employing both brief strenuous and prolonged moderate treadmill exercice. Following 6 days of terbutaline the blood glucose and lactate levels during and following exercise were consistently but not markedly reduced. There was no effect on hemodynamic responses or on blood levels of free fatty acids, nor did exercise tolerance appear to be reduced. The 6-day course of terbutaline did not alter the bronchial sensitivity to inhaled methacholine as measured by spirometry. We conclude that subsensitivity is a characteristic response in most tissues to chronic exogenous adrenergic stimulation. The failure to demonstrate altered methacholine sensitivity may indicate that the adrenergic receptors of the bronchial smooth muscles are an exception to this rule, or, more likely, may reflect the difficulty in demonstrating partial bronchial adrenergic blockade in normal individuals.
A hydrophyte of high relevance, submerged aquatic vegetation (SAV) is of great importance to estuarine environments. SAV helps improve water quality, provides food and shelter for waterfowl, fish, and shellfish, as well as protects shorelines from erosion. In coastal bays most SAV was eliminated by disease in the 1930's. In the late 1960's and 1970's a dramatic decline of all SAV species was correlated with increasing nutrient and sediment inputs from development of surrounding watersheds (MDNP et. al 2004). Currently state programs work to protect and restore existing wetlands, however, increasing development and population pressure continue to degrade and destroy both tidal and non-tidal wetlands and hinder overall development of SAV growth.The focus of this research was to utilize spatial referencing software in the mapping of healthy submerged aquatic vegetation (SAV) habitats. In cooperation with the United States Fish and Wildlife Service (USFWS), and the National Oceanic and Atmospheric Administration (NOAA), students from Elizabeth City State University (ECSU) developed and applied Geographic Information Systems (GIS) skills to evaluate the distribution and abundance of SAV in NorthCarolina's estuarine environments.Utilizing ESRI ArcView, which includes ArcMap, ArcCatalog and ArcToolbox, and the applications of on-screen digitizing, an assessment of vegetation cover was made through the delineation of observable SAV beds in Core Sound, North Carolina. Aerial photography of the identified coastal water bodies was taken at 12,000 feet above mean terrain (AMT) scale 1:24,000. The georeferenced aerial photographs were assessed for obscurities and the SAV beds were digitized. Through the adoption of NOAA guidelines and criteria for benthic habitat mapping using aerial photography for image acquisition and analysis, students delineated SAV beds and developed a GIS spatial database relevant to desired results. This newly created database yielded products in the form of usable shapefiles of SAV polygons, as well as attribute information with location information, area in hectares, and percent coverage of SAV.
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